I was just p*ssed again by not having any decent and simple viewer for animated GIFs, as `animate` from imagemagick often has problems with the framerate. Also I've got no clue why each and every (major) webbrowser does it right, always.

Anyway, I tried gif2apng and the resulting .png works in Opera and Firefox, though not in Chromium and dwb, seems to be a webkit(-gtk) problem.

So I tried with a few imageviewers based on libpng, sxiv and feh to be exact, but they also fail with

Code:

libpng error: internal row size calculation error

Is there just no support for it in libpng, are the apps the problem or what? Any decent way to view animations of this kind?

Edit, libpng is of course merged with USE=apng.
Edit2, gqview at least shows the first frame, but that's it(so the same situation as with gifs)._________________++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>++.<<+++++++++++++++.>.+++.------.--------.>+.>.

Well, in the end it comes down to this - apng extension has never been accepted by libpng upstream (even though it is somewhat useful).
That in turn resulted in it not being supported by gdk-pixbuf loaders and that's what the simple viewers are based upon (at least on gtk side).

Actually, that first link disproves "in the hurry" claim. APNG landed in Firefox 3.0 in 2008. But that bugzilla entry was created in 2004, a few months before Firefox 1.0 release.

If you pay attention, you can see it came just months after they took the existing, working MNG support out of Firebird and made unrealistic code size demands on having it re-included. Demands which the libmng maintainers went to the effort of meeting repeatedly, as they became more and more ridiculous until Mozilla decided to use the nuclear option and fork libpng to get rid of these pesky free software contributors once and for all.

Yes, it's true that the browser went 4 years with reduced functionality, but that was because of the childish attitudes of the libpr0n module owners.

Quote:

If anything, they were extremely slow to add those 1200 lines of C to libpng.

And you can guess how many hundreds of thousands lines of C is in the extremely complex libmng.

I don't have to guess, and I find your vagueness suspect, as the source is right here for anyone to see. As a superset of PNG with JPEG and animation support it only takes twice as many "lines" as libpng, whatever that measure is worth.

Just so everyone is being honest and open here, what is your connection to APNG/Mozilla? Your account is obviously created for this thread and you're being very defensive for no apparent reason.

AFAICT, this comparison is highly unfair, as libmng offered other functionality too (i.e. mentioned in that bug JNG).

Most of that added functionality in MNG is completely useless. Just look at the MAGN chunk that can hold up to 6 different magnification factors (!) for different areas of the image, and up to 5 different magnification methods (!) in each direction. This is insanity.

Or look at the Delta-PNG datastream, its "pixel addition" algorithm is very hard to implement efficiently. Thankfully APNG is limited to standard alpha-blending method that can be found in graphics APIs in all modern systems, and it can be hardware-accelerated. Who wants to process every pixel component of every pixel on a CPU for that "pixel addition"? This is a recipe for draining the batteries. For GIF and APNG you can simply invoke a standard high-level API function to blend one frame on top of another, and the OS will handle hardware-acceleration for you.

[Kayne West]Imma let you finish, but ... anyone knows a decent non-GTK/QT/Browser-viewer for either .gif or .(a)png?[/Kayne West]_________________++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>++.<<+++++++++++++++.>.+++.------.--------.>+.>.